The present invention relates to an apparatus for vibration damping in a motor vehicle.
Nothing in the following discussion of the state of the art is to be construed as an admission of prior art.
German patent application no. DE 39 39 822 A1, published Jun. 6, 1991, discloses a vibration damping system for a motor vehicle, having a control unit for detecting interfering vibration and for controlling an adjuster for operating a vehicle-mounted oscillator in response to the detection of the interfering vibration. The oscillator introduces into the motor vehicle a superimposing and damping, phase-shifted counter vibration in opposition to the interfering vibration. The oscillator is formed by a functional element of the vehicle, e.g. battery or radiator, and the adjuster is realized in the form of a piezo ceramic actuator.
German Pat. No. DE 198 20 617 C2 describes an active vibration damper for motor vehicles which includes struts that are length adjustable on the vehicle underside. The struts are split in midsection and nested within one another like sleeves. Piezoelectric actuators implement a length control of the struts to produce compensating vibration.
European patent application no. EP 0 720 144 A1 describes a system for reducing noise due to vibration in vehicles. Sensors ascertain the motor speed and transmit commensurate information to a control device which includes an amplifier and control several piezoelectric actuators. The piezoelectric actuators are arranged on a body component of the vehicle and secured by gluing.
German patent application no. DE 197 12 292 A1, published Oct. 1, 1998, describes a flange unit for active suppression of vibration. The flange unit is arranged between a vibration generator and a rigid structure and has two flanges, between which an actively controllable pressure-generating element, at least two fiber composite loops, and a tube are arranged. Counter vibrations are generated by elongation and contraction of the pressure-generating element.
German patent application no. DE 199 23 704 A1, published Nov. 23, 2000, describes a vibration damping arrangement having length-adjustable struts which are mounted diagonally across the underside of a body floor. Piezoelectric elements are provided to effect the length adjustments and have incrementally alternating sensor and actuator functions.
It would be desirable and advantageous to provide an improved vibration damping apparatus which is compact in construction and exhibits superior vibration damping properties for incorporation in vibration-causing components of a motor vehicle.